Pasture is a vital asset to your business. It is important both for the profitability of your livestock and cropping enterprises. Assessing the quantity of pasture available can assist with short-term feed budgeting, and help to predict how many days we can run a certain class of stock without having them damage the crop or lose condition.
When talking pasture, we talk in terms of Feed On Offer (FOO), which is every bit of plant material above the ground. This is determined by the amount of Dry Matter Per Hectare or DM/Ha. You may hear agronomists talk of biomass; Dry Matter is essentially this less the water component. The water component is of no use to livestock production. Dry Matter contains all the organic and inorganic nutrient components of feedstuffs needed by livestock for growth and production, hence why in pasture assessment we only measure the DM. It is measured by taking a cutting with a pasture ring, weighing that cutting, then taking a subsample to be dried to measure its DM percentage. The maths then becomes quite simple as we work it over the hectares of the paddock and determine the amount of DSE (Dry Sheep Equivalent) that can be run per day. This allows us to determine either how many head you place on that feed or if you have stock already, how long that feed will last (useful for trading or agistment). This method can be used on both green feed and stubbles.
We can take this a step further and get feed tests done to assess the quality of the FOO. Usually this is predicted at the time of year, but as we start to get later into the season the quality does dwindle. These tests can be particularly helpful during the summer months to ration hay and/or grain which can potentially provide major cost savings.
FOO can be assessed over a twelve-month period in a feed budget to predict how much feed you may have, or how much conserved fodder you may potentially need to buy in or cut. This can only be estimated due to invariable climatic conditions but is just as useful as paddock plans provided for you by our agronomists. It can be taken further by adding a dollar value to both conserved fodder and livestock, and adjusting can determine potential benefits of differing operational methods.
Next time you are questioning how much pasture you have or how much livestock you can run for a set period of time, give us a call. Ask for Duncan Pixley (0447 566 619) or Casey Gilbert (0437 566 646), we are more than happy to help.
Figure 1: Pasture cuts taken of an oat and vetch crop that was 300 to 400 mm in height that revealed a reading of 7.3 Tonnes DM/ Ha which is capable of holding 100 50kg dry ewes on a single hectare for 31 days or 456 50kg dry ewes for a week without damaging the pasture.